<!doctype html>
<html dir='rtl'>
<head>
<style>
.container {
    background-color: #0f0;
    height: 2000px;
    width: 2000px;
}
.floater {
    background-color: #f0f;
    height: 100px;
    left: 0;
    position: fixed;
    top: 0;
    width: 100px;
}
body {
    overflow:hidden;
}
</style>
</head>
<body>

<div class="container">
  <div class="floater" dir="ltr">This box should be fixed to the top-left of the window.
  </div>
</div>

<script>
window.scrollBy(-100, 100);
</script>